Reeling from broadsides on his private background, Mitt Romney rebounded today by indicting President Obama for what he said was the president's misunderstanding of the country and how business works.

Romney's offensive returned the presidential campaign to a debate about policy, and not about tax records, offshore accounts and Bain Capital, the slings that Democrats have hurled at Romney for weeks while the economy sputters.

His powerful speech, which resonated with his supporters and brought them to their feet, was an entirely reworked message that exploited a portion of comments Obama made this weekend. Obama, touting the role of government in helping businesses succeed, said that "if you've got a business, you didn't build that."

"President Obama exposed what he really thinks about free people and the American vision and government, what he really thinks about America itself," Romney told the fiery crowd of about 1,000 today in Irwin, Pa., calling Obama's comment "foolishness" and "insulting to every entrepreneur."

He said it was as if Obama argued that Steve Jobs, Henry Ford, "Papa John" Schnatter, Ray Kroc and Bill Gates didn't start their successful enterprises on their own, but that rather they owed a debt to government for boosting them.

"I'm convinced he wants Americans to be ashamed of success," Romney said.

The figurative backdrop for Romney's assault on Obama is the president's plan to raise taxes on the rich, a proposal that the public generally favors but that is risky anyway because it involves raising taxes at all. Romney's argument, with sprinkles of American exceptionality and individualism, etc., is that government shouldn't take credit when people succeed. If his message sticks, he will have changed the tune of the campaign from his personal taxes to everyone's taxes.

Not that the clamor about Romney's past will gallop into the sunset. Obama's team stuck to its main campaign message today with yet another ad suggesting that Romney is hiding scandalous information in his tax returns that haven't been released. The ad, which cites a growing number of prominent Republicans saying Romney might as well release his records, notes that Romney gave his returns to John McCain in 2008 as part of the vetting process for a running mate, and that McCain eventually chose Sarah Palin, not exactly a flawless candidate.

"What does John McCain know that the American people don't?" the skeptical narrator asks in the advertisement.

McCain later told Politico that he chose Palin over Romney because she was a better candidate, not because Romney's taxes revealed poisonous revelations.

The Romney campaign, which has been fighting off the Obama team's suggestion that he committed a felony by misrepresenting himself on SEC forms, tried to go on offense earlier today by unleashing top surrogate John Sununu to direct the conversation more toward Obama's record on jobs.

Sununu, who was the governor of New Hampshire and George H.W. Bush's chief of staff, teed off on Obama's comment about businesses and unloaded this accusation on a media call, flirting with the sentiments of people who are skeptical of Obama's origin: "The men and women across America who have worked hard to build their businesses from the ground up is how our economy became the envy of the world. It is the American way and I wish this president would learn how to be an American."

What Obama said in his remarks was: "If you were successful, somebody along the line gave you some help. There was a great teacher somewhere in your life. Somebody helped to create this unbelievable American system that we have that allowed you to thrive. Somebody invested in roads and bridges. If you've got a business, you didn't build that. Somebody else made that happen. The Internet didn't get invented on its own. Government research created the Internet so that all the companies could make money off the Internet."

Sununu tried to walk back his accusation -- he said that he meant Obama needs to "learn the American formula for creating business" -- but the Obama campaign issued this statement anyway: "The Romney campaign has officially gone off the deep end. The question is what else they'll pull to avoid answering serious questions about Romney's tenure at Bain Capital and investments in foreign tax havens and offshore accounts. This meltdown and over-the-top rhetoric won't make things better -- it only calls attention to how desperate they are to change the conversation."

Changing the conversation is exactly what has been happening for the past two weeks. But it didn't start with Romney.

Obama, faced with dismal jobs numbers as his opponent hammered him for not shepherding in a recovery, sent his top surrogates to the political talk shows to start a narrative about Romney's background, chiefly his refusal to release tax returns.

Then jumping on a Boston Globe report, the Obama campaign revived another front on Bain, suggesting that Romney committed a felony by appearing to be in charge of the company on SEC forms for three years after he has said he left, in 1999, to run the Olympics.